On an electric golf cart, your motor mounts right to the differential. This is the gearbox between the two axles. Protruding from that unit is a male splined EZGO Input Shaft Kit. It will have 19 splines on the part of the shaft that the motor slides on to. The more significant gear portion of this shaft clocks in at 21 teeth. Make sure you are getting the right one before you order. There is a 22 tooth shaft that will not work. This short shaft puts all the power the motor generates and transfers it to the rear wheels. It interacts with several other gears inside the pumpkin to make it happen. Those gears can be swapped out to gain more torque or speed.This golf cart input shaft is not the hardest thing in the world to install. However, this is not something you should tackle alone. Get a friend to help you, and make sure you have an EZGO OEM manual handy to walk you through the process. Get it all from Buggies Unlimited.